Preheat oven to 350 degrees F.
In a small bowl, combine the butter, bread crumbs, parsley, garlic, almonds, ham, and chopped white mushrooms together. Add salt and pepper, and mix until all ingredients are combined together.
Using a cookie sheet, place the mushroom caps on sheet, add a snail in the center of each mushroom, and cover with the butter mixture. Place the baking sheet in oven and bake for 20 minutes.